There has been relatively little research conducted to demonstrate the effect of diet on patients during sepsis. Many factors are known about metabolism during sepsis for example there is a major increase in whole body protein catabolism during sepsis that is only slightly offset by a minor increase in protein synthesis. The resulting increase in net protein catabolism produces increased excretion of nitrogen as clinically manifested by muscle wasting and weight loss.
In order to prevent these losses of body proteins during sepsis aggressive nutrition support has been advocated to restore positive nitrogen balance. There are little data regarding the optimum amount of protein necessary for recovery from sepsis.
Skeletal muscle wasting and weight loss become clinically evident as sepsis progresses. Nutritional recommendation for septic patients uniformly include increased calories and protein. Certain researchers suggest 1.5 to 2.5 grams of protein per kilogram body weight per day for the moderately stressed patient and 3 grams of protein per kilogram body weight per day for the maximally catabolic patients.
However, there are no data that correlates the amount of protein given to survival rate. The goal of the medical community to date has been simply to supply protein until a positive nitrogen balance has been restored. It was found that total parenteral nutrition solutions that infuse protein at a mean rate of 1.46 grams per kilogram body weight per day in 17 septic patients reduced net protein catabolism from 2.20 grams per kilogram body weight per day to 0.63 grams of kilogram body weight per day. Increasing the rate of protein delivery from 1.1 grams per kilogram per day to 2.2 grams per kilogram per day produced no additional decrease in protein catabolism. In fact, optimal protein sparing was noted at 1.5 kilograms protein per kilogram per day.
It has been shown that protein calorie malnutrition increases the risk of infection. Experimental studies of short term protein deprivation in animals have produced inconsistent results. Conclusions that can be drawn from experimental studies include the observation that resistance to bacterial challenge is diminished by chronic protein restriction. In addition bacterial activity is generally unchanged. Depression of delayed type hypersensitivity has also been confirmed in animal studies.
It has been further shown that diet can affect the immune response system after major assaults to the body. For example, in The Importance of Lipotype in the Diet After Burn, Anals. of Surgery, Vol. 204 No. 1, July 1986 it is reported that the lipids contained in the diet have an effect on the immune response system in burn patients. Specifically, it reports that a diet high in omega 6 fatty acids such as linoleic acid have a significant immunosuppressive effect. On the other hand, diets high in omega 3 fatty acids improve the immune response system. In "The Effect of Dietary Unsaturated Fatty Acids And Indomethacin on Metabolism and Survival After Burn" it is reported that excessive dietary polyunsaturated linoleic acid may influence immunocompetence after burn. In a co-pending application invented by the inventors of the present invention filed Oct. 4, 1988 entitled Method to Improve Immune Response and Resistance to Infection Following Surgery by Diet there is disclosed a presurgery diet composition designed to reduce the risk of infection. The diet is high in omega 6 fatty acids.
Unfortunately none of the diets currently administered to septic patients are designed to have an effect on the infection. They are primarily designed to counter the metabolic effect of sepsis and accordingly may not contribute to the survival rate of the patient.